Objective To investigate the early development of the sinus venosus and the cardiac conduction system (CCS) of human embryonic hearts. Methods Serial transverse sections of 29 human embryonic hearts from Carnegie stage 10 to Carnegie stage 16 (C10-C16) were stained immunohistochemically with antibodies against α-smooth muscle actin(α-SMA),α-sarcomeric actin(α-SCA) and desmin ( DES ). Results During C12 and C13, the sinus venosus formed by confluence of systematic veins at the caudal end of the pericardial cavity could be recognized in the mesenchyme of primitive transverse septum. The mesenchymal cells of the sinus venosus gradually differentiated into α-SCA positive cardiocyocytes. At C14, the sinus venosus was within the pericardial cavity due to expansion of the pericardial cavity and incorporated into the right atrium. Differentiation of DES positive conductive cardiomyocyte was initiated in the right wall of atrio-ventricular canal of C10 embryonic heart and with the development, extended towards the myocardium of the interventricular sulcus to form His bundle, left and right bundle branches as well as the ventricular trabecular myocardium. In the atium, the strong expression of DES was first detected in the dorsal wall of C11 atrium. At C13, unique myocardial band showing α-SCA, α-SMA and DES expression in the left dorsal wall of the sinus venosus were found to be continuous with the basal wall of left atium and the dorsal wall of the atrio-ventricular canal, this band might be related to the development of conduction system from sinoatrial node to atrio-ventricular canal. During C14 to C16, primary conduction pathway of atria with strong DES expression was formed that extended from sinoatrial node along venous valves, DES positive myocardium in the dorsal and ventral walls of the atria to the right atrio-ventricular canal, respectively. Conclusions The mesenchyme of the primitive transverse septum is the heart forming field of human embryos responsible for formation of sinus venosus myocardium, cardiomyocytes are differentiated from mesenchymal cells in the primitive transverse septum and progressively added to the venous pole of the heart tube to form myocardial sinus venosus. The differentiation of CCS of the early human embryo initiates in the atrio-ventricular canal and develops gradually towards the arterial and venous poles of the heart tube. By C16, DES positive embryonic CCS can be clearly recognized morphologically.

Objective To study and search for a balance between the image quality and acquisition speed in tomography of whole body bone scan.Methods Adjustments of acquisition conditions were carried out gradualy every two months since April 2014. The qualities of fused SPECT/CT images were diagnosed by three doctors. Then the picture would be evaluated comprehensively by analyzing image quality and image resolution after adjusting image acquisition conditions.Results Seven kinds of image acquisition conditions taken were in line with diagnostic requirements. The third method is extended to clinical work best.Conclusion To obtain a high colection effi ciency, parameters of bone tomography acquisition can be set a frame of 5 seconds, total 64 (5.625o), automatic probe close and continuous scanning. Also recommends the use of "continuous" instead of "step and shoot" approach in bone SPECT acquisition. tomography, emission-computed, single-photon, bone tomography, program optimization.

Objective:To investigate the value of cardiac color ultrasound combined with cardiac ankle vascular index(CAVI)and ankle brachial index(ABI)in the early diagnosis of coronary heart disease.Methods:A total of 146 patients with coronary heart disease admitted to Leshan People's Hospital from December 2019 to December 2022 were included in the observation group,and 70 healthy persons who underwent physical examination in the hospital during the same period were included in the healthy control group.Both groups underwent cardiac color ultrasound and the examinations of CAVI and ABI.Myocardial performance index(Tei index),ratio of diastolic peak E velocity(E)to late diastolic peak A velocity(A)(E/A),left atrial diameter(LAD),left ventricular ejection fraction(LVEF),CAVI and ABI levels were compared between the two groups.Receiver operating characteristic(ROC)curve was plotted to analyze the values of Tei index,E/A,LAD,LVEF,CAVI and ABI in the alone diagnosis of coronary heart disease.The result of coronary angiography was used as the gold standard,and the consistency was used to analyze the efficacy of the combined diagnosis of Tei index,E/A,LAD,LVEF,CAVI and ABI coronary heart disease.Results:The Tei index,LVEF and CAVI levels in the observation group were significantly higher than those in the healthy control group(t=19.357,25.728,21.766,P<0.05),and the E/A,LAD and ABI levels in the observation group were significantly lower than those in the healthy control group(t=7.721,2.769,10.610,P<0.05),respectively.The ROC analysis proved that Tei index,E/A,LAD,LVEF,CAVI and ABI could be used to diagnose coronary heart disease.The areas under curve(AUC)values of them were 0.914,0.796,0.553,0.950,0.930 and 0.834,respectively.The result of consistency analysis indicated that the sensitivity,specificity,accuracy and Kappa value of the combined diagnosis of Tei index,E/A,LAD,LVEF,CAVI and ABI were respectively 0.986,0.929,0.968 and[0.925(P<0.05)]in diagnosing coronary heart disease.Conclusion:Tei index,E/A,LAD,LVEF,CAVI and ABI can be used to diagnose coronary heart disease,and the combined diagnosis of them has higher efficiency.